Effect of Inlet Velocity on Wall Superheat

The point of ONB located at the channel exit corresponds to minimum heat flux at which the boiling incipience is possible for the channel of the given length. Kennedy et al. (2000) presented the measurements that were carried out at different values of the inlet average velocity t/m, whereas the inlet temperature Tin, was constant. 

To estimate the value of the bulk liquid temperature at ONB in conventional size channels, as well as in micro-channels the energy and continuity equations should be considered. 

Restricting our consideration analysis of the developed flow we rewrite Eqs. (6.17) and (6.18) in the form 

Omitting in Eq. (6.23) the last term that allows for axial heat transfer, Eq. (6.23) may be expressed  

Equation (6.27) was obtained for circular channels. Rectangular channels with four or three conductive walls are shown in Eig. 6.10. 

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